This year the annual 4th of July fair in St. Louis will add a zip line billed as the longest tallest mobile zip line which will move riders from one end to the other at 25 mph in ten seconds. Boy I'd like to try this. However I'd wager the lines will be really long for this. It will be set up on Lagoon Drive at the west entrance to the fair and the cost will be ten dollars.
Maybe getting there really early with my GoPro wearable video cam would nudge me into trying this.